by Yao Jian. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 109-112). / Abstract --- p.i / Acknowledgments --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Basic Concepts And Related Work --- p.6 / Chapter 2.1 --- Codeset and Codeset Conversion --- p.7 / Chapter 2.2 --- HTML Language --- p.10 / Chapter 2.3 --- HTTP Protocol --- p.13 / Chapter 2.4 --- I18N And LION --- p.18 / Chapter 2.5 --- Proxy Server --- p.19 / Chapter 2.6 --- Related Work --- p.20 / Chapter 3 --- Design Principles And System Architecture --- p.23 / Chapter 3.1 --- Use of Existing Web System --- p.23 / Chapter 3.1.1 --- Protocol --- p.23 / Chapter 3.1.2 --- Avoid Duplication of Documents for Different Codesets --- p.25 / Chapter 3.1.3 --- Support On-line Codeset Conversion Facility --- p.27 / Chapter 3.1.4 --- Provide Internationalized Interface of Web Browser --- p.28 / Chapter 3.2 --- Our Approach --- p.29 / Chapter 3.2.1 --- Enhancing the Existing Browsers and Servers --- p.30 / Chapter 3.2.2 --- Incorporating Proxies in Our Scheme --- p.32 / Chapter 3.2.3 --- Automatic Codeset Conversion --- p.34 / Chapter 3.3 --- Overall System Architecture --- p.38 / Chapter 3.3.1 --- Architecture of Our Web System --- p.38 / Chapter 3.3.2 --- Flexibility of Our Design --- p.40 / Chapter 3.3.3 --- Which side do the codeset conversion? --- p.42 / Chapter 3.3.4 --- Caching --- p.42 / Chapter 4 --- Design Details of An Enhanced Server --- p.44 / Chapter 4.1 --- Architecture of The Enhanced Server --- p.44 / Chapter 4.2 --- Procedure on Processing Client's Request --- p.45 / Chapter 4.3 --- Modifications of The Enhanced Server --- p.48 / Chapter 4.3.1 --- Interpretation of Client's Codeset Announcement --- p.48 / Chapter 4.3.2 --- Codeset Identification of Web Documents on the Server --- p.49 / Chapter 4.3.3 --- Codeset Notification to the Web Client --- p.52 / Chapter 4.3.4 --- Codeset Conversion --- p.54 / Chapter 4.4 --- Experiment Results --- p.54 / Chapter 5 --- Design Details of An Enhanced Browser --- p.58 / Chapter 5.1 --- Architecture of The Enhanced Browser --- p.58 / Chapter 5.2 --- Procedure on Processing Users' Requests --- p.61 / Chapter 5.3 --- Event Management and Handling --- p.63 / Chapter 5.3.1 --- Basic Control Flow of the Browser --- p.63 / Chapter 5.3.2 --- Event Handlers --- p.64 / Chapter 5.4 --- Internationalization of Browser Interface --- p.75 / Chapter 5.4.1 --- Locale --- p.76 / Chapter 5.4.2 --- Resource File --- p.77 / Chapter 5.4.3 --- Message Catalog System --- p.79 / Chapter 5.5 --- Experiment Result --- p.85 / Chapter 6 --- Another Scheme - CGI --- p.89 / Chapter 6.1 --- Form and CGI --- p.90 / Chapter 6.2 --- CGI Control Flow --- p.96 / Chapter 6.3 --- Automatic Codeset Detection --- p.96 / Chapter 6.3.1 --- Analysis of code range for GB and Big5 --- p.98 / Chapter 6.3.2 --- Control Flow of Automatic Codeset Detection --- p.99 / Chapter 6.4 --- Experiment Results --- p.101 / Chapter 7 --- Conclusions and Future Work --- p.104 / Chapter 7.1 --- Current Status --- p.105 / Chapter 7.2 --- System Efficiency --- p.106 / Chapter 7.3 --- Future Work --- p.107 / Bibliography --- p.109 / Chapter A --- Programmer's Guide --- p.113 / Chapter A.1 --- Data Structure --- p.113 / Chapter A.2 --- Calling Sequence of Functions --- p.114 / Chapter A.3 --- Modification of Souce Code --- p.116 / Chapter A.4 --- Modification of Resources --- p.133 / Chapter B --- User Manual --- p.135

by Chan Kwong Wing Raymond. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 115-123). / Acknowledgments --- p.i / Table of Contents --- p.ii-v / List of Tables --- p.vi / List of Figures --- p.vii / Abstract --- p.1 / Chapter Chapter 1 : --- Introduction / Chapter 1.1 --- An Introduction to Video Compression --- p.3 / Chapter 1.2 --- Overview of Problems --- p.4 / Chapter 1.2.1 --- Analog Video and Digital Problems --- p.4 / Chapter 1.2.2 --- Low Bit Rate Application Problems --- p.4 / Chapter 1.2.3 --- Real Time Video Compression Problems --- p.5 / Chapter 1.2.4 --- Source Coding and Channel Coding Problems --- p.6 / Chapter 1.2.5 --- Bit-rate and Quality Problems --- p.7 / Chapter 1.3 --- Organization of the Thesis --- p.7 / Chapter Chapter 2 : --- Background and Related Work / Chapter 2.1 --- Introduction --- p.9 / Chapter 2.1.1 --- Analog Video --- p.9 / Chapter 2.1.2 --- Digital Video --- p.10 / Chapter 2.1.3 --- Color Theory --- p.10 / Chapter 2.2 --- Video Coding --- p.12 / Chapter 2.2.1 --- Predictive Coding --- p.12 / Chapter 2.2.2 --- Vector Quantization --- p.12 / Chapter 2.2.3 --- Subband Coding --- p.13 / Chapter 2.2.4 --- Transform Coding --- p.14 / Chapter 2.2.5 --- Hybrid Coding --- p.14 / Chapter 2.3 --- Transform Coding --- p.15 / Chapter 2.3.1 --- Discrete Cosine Transform --- p.16 / Chapter 2.3.1.1 --- 1-D Fast Algorithms --- p.16 / Chapter 2.3.1.2 --- 2-D Fast Algorithms --- p.17 / Chapter 2.3.1.3 --- Multidimensional DCT Algorithms --- p.17 / Chapter 2.3.2 --- Quantization --- p.18 / Chapter 2.3.3 --- Entropy Coding --- p.18 / Chapter 2.3.3.1 --- Huffman Coding --- p.19 / Chapter 2.3.3.2 --- Arithmetic Coding --- p.19 / Chapter Chapter 3 : --- Existing Compression Scheme / Chapter 3.1 --- Introduction --- p.20 / Chapter 3.2 --- Motion JPEG --- p.20 / Chapter 3.3 --- MPEG --- p.20 / Chapter 3.4 --- H.261 --- p.22 / Chapter 3.5 --- Other Techniques --- p.23 / Chapter 3.5.1 --- Fractals --- p.23 / Chapter 3.5.2 --- Wavelets --- p.23 / Chapter 3.6 --- Proposed Solution --- p.24 / Chapter 3.7 --- Summary --- p.25 / Chapter Chapter 4 : --- Fast 3D-DCT Algorithms / Chapter 4.1 --- Introduction --- p.27 / Chapter 4.1.1 --- Motivation --- p.27 / Chapter 4.1.2 --- Potentials of 3D DCT --- p.28 / Chapter 4.2 --- Three Dimensional Discrete Cosine Transform (3D-DCT) --- p.29 / Chapter 4.2.1 --- Inverse 3D-DCT --- p.29 / Chapter 4.2.2 --- Forward 3D-DCT --- p.30 / Chapter 4.3 --- 3-D FCT (3-D Fast Cosine Transform Algorithm --- p.30 / Chapter 4.3.1 --- Partitioning and Rearrangement of Data Cube --- p.30 / Chapter 4.3.1.1 --- Spatio-temporal Data Cube --- p.30 / Chapter 4.3.1.2 --- Spatio-temporal Transform Domain Cube --- p.31 / Chapter 4.3.1.3 --- Coefficient Matrices --- p.31 / Chapter 4.3.2 --- 3-D Inverse Fast Cosine Transform (3-D IFCT) --- p.32 / Chapter 4.3.2.1 --- Matrix Representations --- p.32 / Chapter 4.3.2.2 --- Simplification of the calculation steps --- p.33 / Chapter 4.3.3 --- 3-D Forward Fast Cosine Transform (3-D FCT) --- p.35 / Chapter 4.3.3.1 --- Decomposition --- p.35 / Chapter 4.3.3.2 --- Reconstruction --- p.36 / Chapter 4.4 --- The Fast Algorithm --- p.36 / Chapter 4.5 --- Example using 4x4x4 IFCT --- p.38 / Chapter 4.6 --- Complexity Comparison --- p.43 / Chapter 4.6.1 --- Complexity of Multiplications --- p.43 / Chapter 4.6.2 --- Complexity of Additions --- p.43 / Chapter 4.7 --- Implementation Issues --- p.44 / Chapter 4.8 --- Summary --- p.46 / Chapter Chapter 5 : --- Quantization / Chapter 5.1 --- Introduction --- p.49 / Chapter 5.2 --- Dynamic Ranges of 3D-DCT Coefficients --- p.49 / Chapter 5.3 --- Distribution of 3D-DCT AC Coefficients --- p.54 / Chapter 5.4 --- Quantization Volume --- p.55 / Chapter 5.4.1 --- Shifted Complement Hyperboloid --- p.55 / Chapter 5.4.2 --- Quantization Volume --- p.58 / Chapter 5.5 --- Scan Order for Quantized 3D-DCT Coefficients --- p.59 / Chapter 5.6 --- Finding Parameter Values --- p.60 / Chapter 5.7 --- Experimental Results from Using the Proposed Quantization Values --- p.65 / Chapter 5.8 --- Summary --- p.66 / Chapter Chapter 6 : --- Entropy Coding / Chapter 6.1 --- Introduction --- p.69 / Chapter 6.1.1 --- Huffman Coding --- p.69 / Chapter 6.1.2 --- Arithmetic Coding --- p.71 / Chapter 6.2 --- Zero Run-Length Encoding --- p.73 / Chapter 6.2.1 --- Variable Length Coding in JPEG --- p.74 / Chapter 6.2.1.1 --- Coding of the DC Coefficients --- p.74 / Chapter 6.2.1.2 --- Coding of the DC Coefficients --- p.75 / Chapter 6.2.2 --- Run-Level Encoding of the Quantized 3D-DCT Coefficients --- p.76 / Chapter 6.3 --- Frequency Analysis of the Run-Length Patterns --- p.76 / Chapter 6.3.1 --- The Frequency Distributions of the DC Coefficients --- p.77 / Chapter 6.3.2 --- The Frequency Distributions of the DC Coefficients --- p.77 / Chapter 6.4 --- Huffman Table Design --- p.84 / Chapter 6.4.1 --- DC Huffman Table --- p.84 / Chapter 6.4.2 --- AC Huffman Table --- p.85 / Chapter 6.5 --- Implementation Issue --- p.85 / Chapter 6.5.1 --- Get Category --- p.85 / Chapter 6.5.2 --- Huffman Encode --- p.86 / Chapter 6.5.3 --- Huffman Decode --- p.86 / Chapter 6.5.4 --- PutBits --- p.88 / Chapter 6.5.5 --- GetBits --- p.90 / Chapter Chapter 7 : --- "Contributions, Concluding Remarks and Future Work" / Chapter 7.1 --- Contributions --- p.92 / Chapter 7.2 --- Concluding Remarks --- p.93 / Chapter 7.2.1 --- The Advantages of 3D DCT codec --- p.94 / Chapter 7.2.2 --- Experimental Results --- p.95 / Chapter 7.1 --- Future Work --- p.95 / Chapter 7.2.1 --- Integer Discrete Cosine Transform Algorithms --- p.95 / Chapter 7.2.2 --- Adaptive Quantization Volume --- p.96 / Chapter 7.2.3 --- Adaptive Huffman Tables --- p.96 / Appendices: / Appendix A : The detailed steps in the simplification of Equation 4.29 --- p.98 / Appendix B : The program Listing of the Fast DCT Algorithms --- p.101 / Appendix C : Tables to Illustrate the Reording of the Quantized Coefficients --- p.110 / Appendix D : Sample Values of the Quantization Volume --- p.111 / Appendix E : A 16-bit VLC table for AC Run-Level Pairs --- p.113 / References --- p.115

by Ho, Hau Lai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 97-103). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview of Attractor Image Coding --- p.2 / Chapter 1.2 --- Scope of Thesis --- p.3 / Chapter 2 --- Fundamentals of Attractor Coding --- p.6 / Chapter 2.1 --- Notations --- p.6 / Chapter 2.2 --- Mathematical Preliminaries --- p.7 / Chapter 2.3 --- Partitioned Iterated Function Systems --- p.10 / Chapter 2.3.1 --- Mathematical Formulation of the PIFS --- p.12 / Chapter 2.4 --- Attractor Coding using the PIFS --- p.16 / Chapter 2.4.1 --- Quadtree Partitioning --- p.18 / Chapter 2.4.2 --- Inclusion of an Orthogonalization Operator --- p.19 / Chapter 2.5 --- Coding Examples --- p.21 / Chapter 2.5.1 --- Evaluation Criterion --- p.22 / Chapter 2.5.2 --- Experimental Settings --- p.22 / Chapter 2.5.3 --- Results and Discussions --- p.23 / Chapter 2.6 --- Summary --- p.25 / Chapter 3 --- Attractor Coding with Adjacent Block Parameter Estimations --- p.27 / Chapter 3.1 --- δ-Minimum Edge Difference --- p.29 / Chapter 3.1.1 --- Definition --- p.29 / Chapter 3.1.2 --- Theoretical Analysis --- p.31 / Chapter 3.2 --- Adjacent Block Parameter Estimation Scheme --- p.33 / Chapter 3.2.1 --- Joint Optimization --- p.34 / Chapter 3.2.2 --- Predictive Coding --- p.36 / Chapter 3.3 --- Algorithmic Descriptions of the Proposed Scheme --- p.39 / Chapter 3.4 --- Experimental Results --- p.40 / Chapter 3.5 --- Summary --- p.50 / Chapter 4 --- Attractor Coding using Lapped Partitioned Iterated Function Sys- tems --- p.51 / Chapter 4.1 --- Lapped Partitioned Iterated Function Systems --- p.53 / Chapter 4.1.1 --- Weighting Operator --- p.54 / Chapter 4.1.2 --- Mathematical Formulation of the LPIFS --- p.57 / Chapter 4.2 --- Attractor Coding using the LPIFS --- p.62 / Chapter 4.2.1 --- Choice of Weighting Operator --- p.64 / Chapter 4.2.2 --- Range Block Preprocessing --- p.69 / Chapter 4.2.3 --- Decoder Convergence Analysis --- p.73 / Chapter 4.3 --- Local Domain Block Searching --- p.74 / Chapter 4.3.1 --- Theoretical Foundation --- p.75 / Chapter 4.3.2 --- Local Block Searching Algorithm --- p.77 / Chapter 4.4 --- Experimental Results --- p.79 / Chapter 4.5 --- Summary --- p.90 / Chapter 5 --- Conclusion --- p.91 / Chapter 5.1 --- Original Contributions --- p.91 / Chapter 5.2 --- Subjects for Future Research --- p.92 / Chapter A --- Fundamental Definitions --- p.94 / Chapter B --- Appendix B --- p.96 / Bibliography --- p.97

Zheng Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 63-66). / Abstracts in English and Chinese. / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Review of space-time coding and blind channel estimation --- p.1 / Chapter 1.2 --- Introduction of space-time coding system --- p.4 / Chapter 1.3 --- Diversity gain of space-time coding --- p.6 / Chapter 1.4 --- Re-estimation --- p.7 / Chapter 1.5 --- Notations --- p.8 / Chapter 1.6 --- Outline of thesis --- p.8 / Chapter 2. --- Estimation for BPSK Signals --- p.10 / Chapter 2.1 --- Introduction to maximum likelihood estimation --- p.10 / Chapter 2.2 --- System model --- p.11 / Chapter 2.3 --- Deterministic ML algorithm --- p.14 / Chapter 2.4 --- Re-estimation --- p.16 / Chapter 2.5 --- Application to other constellations --- p.18 / Chapter 2.6 --- Simulation results --- p.18 / Chapter 2.7 --- Summary --- p.21 / Chapter 3. --- Estimation for Flat Fading Channels --- p.22 / Chapter 3.1 --- Introduction of constant modulus algorithm (CMA) --- p.22 / Chapter 3.2 --- System model for flat fading channels --- p.24 / Chapter 3.3 --- Blind estimation with CMA --- p.26 / Chapter 3.3.1 --- Problem statement --- p.26 / Chapter 3.3.2 --- Estimating channel with CMA --- p.28 / Chapter 3.3.3 --- Solving the ambiguity problem --- p.32 / Chapter 3.4 --- Re-estimation for flat fading channels --- p.39 / Chapter 3.5 --- Estimation algorithm --- p.39 / Chapter 3.6 --- Application to multi-antenna system --- p.41 / Chapter 3.7 --- Simulation results --- p.42 / Chapter 3.8 --- Summary --- p.46 / Chapter 4. --- Estimation lor Frequency Selective Fading Channels --- p.48 / Chapter 4.1 --- Introduction of space-time coded OFDM --- p.48 / Chapter 4.2 --- System model --- p.51 / Chapter 4.3 --- Estimation Algorithm --- p.54 / Chapter 4.4 --- Simulation results --- p.56 / Chapter 4.5 --- Summary --- p.59 / Chapter 5. --- Conclus ions and Future Work --- p.60 / Chapter 5.1 --- Conclusions --- p.60 / Chapter 5.2 --- Future work --- p.61 / Bibliography: --- p.63

Zheng, Xiaoting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 64-69). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Rayleigh Fading --- p.1 / Chapter 1.2 --- Transmission Schemes --- p.2 / Chapter 1.2.1 --- Frequency Division Multiple Access(FDMA) --- p.2 / Chapter 1.2.2 --- Time Division Multiple Access(TDMA) --- p.3 / Chapter 1.2.3 --- Code Division Multiple Access(CDMA) --- p.5 / Chapter 1.2.4 --- The Broadcast Channel --- p.5 / Chapter 1.3 --- Cooperative Transmissions --- p.9 / Chapter 1.3.1 --- Relaying Protocols --- p.10 / Chapter 1.4 --- Outline of Thesis --- p.12 / Chapter 2 --- Background Study --- p.13 / Chapter 2.1 --- Superposition Coding --- p.13 / Chapter 2.2 --- Cooperative Transmission --- p.15 / Chapter 2.2.1 --- Single Source Single Destination --- p.15 / Chapter 2.2.2 --- Multiple Sources Single Destination --- p.16 / Chapter 2.2.3 --- Single Source Multiple Destinations --- p.17 / Chapter 2.2.4 --- Multiple Sources Multiple Destinations --- p.17 / Chapter 2.3 --- Power Minimization --- p.18 / Chapter 2.3.1 --- Power Minimization in Code-Multiplexing System --- p.19 / Chapter 2.3.2 --- Power Minimization in Frequency-multiplexing System --- p.19 / Chapter 2.3.3 --- Power Minimization in Time-Multiplexing System --- p.20 / Chapter 3 --- Sum Power Minimization with Superposition Coding --- p.21 / Chapter 3.1 --- System Model --- p.22 / Chapter 3.2 --- Superposition Coding Scheme --- p.22 / Chapter 3.2.1 --- Optimal Superposition Coding Scheme --- p.22 / Chapter 3.2.2 --- Sub-optimal Superposition Coding Scheme --- p.27 / Chapter 3.3 --- Performance Evaluation --- p.30 / Chapter 3.4 --- Assignment Examples for Superposition Coding Scheme --- p.33 / Chapter 4 --- Source-cooperated Transmission in a Wireless Cluster --- p.42 / Chapter 4.1 --- System Model --- p.42 / Chapter 4.2 --- Selection Protocol --- p.44 / Chapter 4.2.1 --- Protocol Description and Problem Formulation --- p.44 / Chapter 4.2.2 --- Distributed Selection Algorithm --- p.46 / Chapter 4.2.3 --- Low Rate Regime --- p.50 / Chapter 4.3 --- Simulation Results --- p.52 / Chapter 4.3.1 --- Simulation Configuration --- p.53 / Chapter 4.3.2 --- Cases with a Smaller Feasible Solution Set --- p.53 / Chapter 4.3.3 --- Cases with a Larger Feasible Solution Set --- p.56 / Chapter 5 --- Conclusion and Future Work --- p.61 / Chapter 5.1 --- Conclusion --- p.61 / Chapter 5.2 --- Future Work --- p.62 / Chapter 5.2.1 --- Fairness --- p.62 / Chapter 5.2.2 --- Distributed Algorithm --- p.63 / Chapter 5.2.3 --- Game Theory --- p.63 / Chapter 5.2.4 --- Distributed Information --- p.63 / Bibliography --- p.64

Le, Jilin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 57-59). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- How Many Packets Can We Encode? --- p.2 / Chapter 1.2 --- Coding-Aware Routing --- p.3 / Chapter 2 --- Related Work --- p.6 / Chapter 3 --- Performance Analysis of COPE --- p.8 / Chapter 3.1 --- Introduction --- p.8 / Chapter 3.2 --- Coding Structure: Characterization and Properties --- p.9 / Chapter 3.2.1 --- Assumptions and notations --- p.9 / Chapter 3.2.2 --- Optimum Throughput in a Coding Structure --- p.10 / Chapter 3.2.3 --- The Upper Bound of Maximum Encoding Number --- p.11 / Chapter 3.3 --- Coding Performance under Random Access Link-Scheduling --- p.14 / Chapter 3.3.1 --- Key Intuition --- p.14 / Chapter 3.3.2 --- Calculating the Average Encoding Number --- p.15 / Chapter 3.3.3 --- Case Studies --- p.18 / Chapter 3.3.4 --- Will Delaying Strategy at the Coding Node Help? --- p.21 / Chapter 3.4 --- Fundamental Limits of the Coding Scheme --- p.22 / Chapter 3.5 --- Verification of the Analysis --- p.27 / Chapter 3.5.1 --- Simulation Results in a Single Coding Structure --- p.27 / Chapter 3.5.2 --- Simulation Results under 802.11 and General Networks --- p.29 / Chapter 3.6 --- Potential Applications --- p.31 / Chapter 3.7 --- Conclusion --- p.31 / Chapter 4 --- Distributed Coding-Aware Routing --- p.33 / Chapter 4.1 --- Introduction --- p.33 / Chapter 4.2 --- "The ""CodingH+Routing"" Discovery" --- p.34 / Chapter 4.2.1 --- Assumptions --- p.34 / Chapter 4.2.2 --- General Coding Conditions --- p.35 / Chapter 4.2.3 --- "Distributed ""Coding+Routing"" Discovery" --- p.36 / Chapter 4.2.4 --- An Illustrative Example --- p.38 / Chapter 4.2.5 --- Overheads of Coding+Routing Discovery --- p.39 / Chapter 4.3 --- Defining Coding-Aware Routing Metric --- p.40 / Chapter 4.3.1 --- Review of Current Routing Metrics --- p.40 / Chapter 4.3.2 --- Desirable Properties of Coding-aware Routing Metric --- p.42 / Chapter 4.3.3 --- Assumptions on Encoded Transmission --- p.42 / Chapter 4.3.4 --- "Interpreting the ""Free-Ride"" Benefit" --- p.43 / Chapter 4.3.5 --- Modified Queue Length --- p.44 / Chapter 4.3.6 --- MIQ: Modified Interference Queue Length --- p.46 / Chapter 4.3.7 --- CRM: Coding-aware Routing Metric --- p.47 / Chapter 4.4 --- Implementation Details --- p.48 / Chapter 4.5 --- Simulation Results --- p.49 / Chapter 4.5.1 --- Results from Illustrative Scenarios --- p.50 / Chapter 4.5.2 --- Results from Mesh Networks --- p.52 / Chapter 4.6 --- Conclusion --- p.55 / Chapter 5 --- Conclusion --- p.56 / Bibliography --- p.57

As the bandwidth has become much cheaper in the recent years, video applications are more popular than before. However, the demand of high video resolution, high frame rate, or high bit-depth has continued to increase more rapidly than the cost of video transmission and storage bandwidth. It requires more efficient compression techniques, and hence many international video coding standards are developed in the past decades such as the MPEG-1/2/4 part 2, H.264/MPEG-4 part 10 AVC and the latest High Efficiency Video Coding (HEVC) standards. The main objective of this thesis is to consider the problems in analyzing the characteristics of video signals and providing efficient compression and transmission solutions in both H.264/AVC and HEVC video systems. Three main parts of this work are briey summarized below. / The first part concerns transform coding. Transform coding has been widely used to remove spatial redundancy of prediction residuals in the modern video coding standards. However, since the residual blocks exhibit diverse characteristics in a video sequence, conventional sinusoidal transforms with fixed transform kernels may result in low coding efficiency. To tackle this problem, we propose a novel content adaptive transform framework for H.264/AVC-based video coding. We propose to utilize pixel rearrangement to dynamically adjust the transform kernels to adapt to the video signals. In addition, unlike the traditional adaptive transforms, the proposed method obtains the transform kernels from the reconstructed block, and hence it consumes only one logic indicator for each transform unit. Moreover, a spiral-scanning method is developed to reorder the transform coefficients for better entropy coding. Experimental results on the Key Technical Area (KTA) platform show that the proposed method can achieve a significant bits reduction under both the all-intra and low-delay configurations. / The second part investigates the next-generation video coding. Due to increase of display resolution from High-definition (HD) to Ultra-HD, how to efficiently compress the Ultra-HD signals are essential in the development of future video compression systems. High-resolution video coding benefits from a larger prediction block size and thereof transform and quantization of prediction residues. However, in the current HEVC video coding standard, the maximum coding tree unit (CTU) size is 64x64, which can limit a possible larger prediction block in Ultra-HD video coding, and hence cause negative effects on coding efficiency. Thus, we propose to extend CTU to a super coding unit (SCU) for next-generation video coding, and two separate coding structures are designed to encode a SCU, including Direct-CTU and SCU-to-CTU modes. In Direct-CTU, an SCU is first split into a number of predefined CTUs, and then, the best encoding parameters are searched from the current CTU to the possible minimum coding unit (MCU). Similarly, in SCU-to-CTU, the best encoding parameters are searched from SCU to CTU. In addition, the adaptive loop filter (ALF) and sample adaptive offset (SAO) methods are investigated in SCU based video coding framework. We propose to change the filtering control from SCU level to the coding unit (CU) level, and an improved CU level ALF signaling method is also proposed to further improve the coding efficiency. Furthermore, an adaptive SAO block method is also proposed, and this flexibility of SAO blocks can further improve the performance of the traditional method in the Ultra HD video coding. / In the last part, we explore the bit rate control of video transmission. Rate control serves as an important technique to regulate the bit rate of video transmission over a limited bandwidth and to maximize the overall video quality. Video quality fluctuation plays a key role in human visual perception, and hence many rate control algorithms have been widely developed to maintain a consistent quality for video communication. We propose a novel rate control framework based on the Lagrange multiplier in HEVC. With the assumption of constant quality control, a new relationship between the distortion and the Lagrange multiplier is established. Based on the proposed distortion model and buffer status, we obtain a computationally feasible solution to the problem of minimizing the distortion variation across video frames at the coding tree unit level. Extensive simulation results show that our method outperforms the HEVC rate control by providing a more accurate rate regulation, lower video quality fluctuation and stabler buffer fullness. / 近些年，隨著帶寬費用變得越來越便宜，各種視頻應用比以前更為流行了。然而，人們對于高視頻分辨率，高幀率，或更高比特像素的需求增加了視頻傳輸和存儲帶寬的成本。滿足這樣的需求需要更有效的壓縮技術，因此在過去的幾十年裏，很多國際視頻編碼標准被開發出來，例如MPEG-1/2/4 part2, H264/MPEG-4 part 10 AVC和最新高效視頻編碼標准(HEVC)。本論文的主要目的是研究視頻信號的特點，在H.264和HEVC視頻系統中提供高效的壓縮和傳輸解決方案。論文分三部分，簡要總結如下。 / 第壹部分涉及變換編碼。在現代視頻編碼標准中，變換編碼已被廣泛用于消除預測殘差的空間冗余度。然而，由于在視頻序列中的預測殘差塊有著不同的特性，傳統的變換采用固定變換矩陣可能會導致低的編碼效率。為了解決這個問題，我們提出了壺種新的基于內容自適應變換方案的視頻編碼框架。我們利用重排像素，動態調整的變換矩陣以適應當前的視頻信號。此外，與傳統的自適應變換不同之處在于，我們所提出的方法得到的變換矩陣不需要傳輸到解碼端，而它僅消耗壺個邏輯單元指示當前變換矩陣。此外，我們提出了相應的變換系數掃描方法以達到更有效的熵編碼。在關鍵技術領域(KTA)平台，實驗結果表明本方法可以有效的改善幀內和低延遲的配置下的編碼效率。 / 第二部分探討了新壹代視頻編碼。由于主流顯示分辨率從高清到超高清的變化，如何有效地壓縮超高清視頻信號是未來視頻壓縮技術發展的關鍵。超高分辨率視頻編碼的好處在于可從壹個更大的預測塊對其預測殘差進行變換和量化。然而，在目前HEVC視頻編碼標準，最大編碼榭單元尺寸（CTU）是64x64，其可能限制較大的預測塊，從而影響編碼效率。因此，我們提出了擴展CTU為SCU。其中編碼壹個SCU可能用到兩個獨立的編碼模式，包括Direct-CTU和SCU-to-CTU。在Direct-CTU模式中，SCU被分割成許多預定義的CTUs，然後，最佳的編碼參數搜索範圍為CTU到MCU。同樣，在SCU-to-CTU模式中，最佳的編碼參數搜索範圍是SCU到CTU。此外，自適應環路濾波器（ALF）和自適應采偏移（SAO）在新的SCU編碼框架下進行了研究。我們提出濾波控制從SCU級別更改為CU級別，並提出了新的ALF信號傳送方法進壹步提高傳統的方法在超高清視頻編碼的中性能。 / 在最後壹部分，我們探討了視頻傳輸中的碼率控制。碼率控制作為壹種重要的技術，在有限的帶寬條件下，以最大限度地提高整體的視頻質量。視頻質量波動在人眼視覺感知中起著至關重要的作用，因此許多碼率控制方法得到了廣泛的發展，以追求提供穩定的視頻通信質量。我們提出了壹個新基于HEVC拉格日乘數碼率控制框架。在平穩視頻質量的假設下，我們提出了壹種新的失真和拉格日乘子之間的關係。基于新提出的失真模型和緩沖區的狀態，我們得到壹個計算上可行的解決方案，以最大限度地減少在編碼榭單元級的視頻幀的失真變化。大量的仿真結果表明，我們的方法優于HEVC的碼率控制，它可以提供更精確的碼率調節，降低視頻質量波動，以及維護穩定的緩沖區占有率。 / Wang, Miaohui. / Thesis Ph.D. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 158-164). / Abstracts and acknowledgements also in Chinese. / Title from PDF title page (viewed on 11, October, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

This thesis investigates the fundamental building blocks of physical-layer network coding (PNC). Most prior work on PNC focused on its application in a simple two-way-relay channel (TWRC) consisting of three nodes only. Studies of the application of PNC in general networks are relatively few. This thesis attempts to fill this gap by three steps: / In first step, we put forth two ideas: 1) A general network can be decomposed into small building blocks of PNC, referred to as the PNC atoms, for scheduling of PNC transmissions. 2) We identify nine PNC atoms, with TWRC being one of them. / In second step, we formulate the PNC scheduling problem as a linear program based on the atom-decomposition. Three major results are got from performance valuation: First, the throughput performance of PNC is shown to be significantly better than those of the traditional multi-hop scheme and the conventional network coding scheme. For example, under heavy traffic volume, PNC can achieve 100% throughput gain relative to the traditional multi-hop scheme. Second, PNC decomposition based on a variety of different PNC atoms can yield much better performance than PNC decomposition based on the TWRC atom alone. Third, three out of the nine atoms are most important to good performance. Specifically, the decomposition based on these three atoms is good enough most of the time, and it is not necessary to use the other six atoms. We have also designed a low-overhead MAC protocol to coordinate the transmissions of different nodes according to the scheduling results of PNC decomposition. / In third step, we investigate ARQ (Automatic Repeat request) designs for PNC systems (building blocks). The above building blocks studies assumed what is sent always get received. In practice, that is not the case. Error control is needed to ensure reliable communication. Here, we focus on the use of ARQ to ensure reliable PNC communication. In some of PNC building blocks, receivers can obtain side information through overhearing. Although such overheard information is not the target information that the receivers desire, the receivers can exploit the overheard information together with a network-coded packet received to obtain a desired native packet. This leads to throughput gain. The availability of overhead information and its potential exploitation make the ARQ design of a network-coded system different from that of a non-network-coded system. In this these, we lay out the fundamental considerations for such ARQ design: 1) We address how to track the stored coded packets and overheard packets to increase the chance of packet extraction, and derive the throughput gain achieved by tracking 2) We investigate two variations of PNC ARQ, coupled and non-coupled ARQs, and prove that non-coupled ARQ is more efficient; 3) We show how to optimize parameters in PNC ARQ—specifically the window size and ACK frequency—to minimize the throughput degradation caused by ACK feedback overhead and wasteful retransmissions due to lost ACK. Our throughput analyses and performance evaluations indicate that for our investigated atoms, our PNC ARQ yield considerable throughput gains. / In a conclusion, the decomposition based on a variety of different PNC atoms that we investigated can yield much better performance than the traditional multi-hop scheme and the conventional network coding scheme. In practical wireless systems where transmission errors can occur, adopting our PNC ARQ design can efficiently maintain the throughput gain achieved by PNC atom decomposition. / 本論文致力於研究基於物理層網絡編碼（PNC, Physical-layer Network Coding）的基礎構建模塊。現有的物理層網絡編碼的研究大都基於最簡單的雙向中繼信道（TWRC）系統上。TWRC是一個由三節點組成的小型通信網絡——兩個終端節點通過一個中繼節點通信。而基於大型網絡應用的PNC研究卻非常少見。為了填補這一空白，本論文分三步驟進行PNC研究: / 研究第一步，我們提出兩個問題： 1）為了PNC網絡調度，一個網絡可以被分解成若干小的PNC基礎構建模塊。 2）我們發現了除9個基本的PNC構建模塊（包含PNC TWRC）。 / 研究第二步，我們通過建立基於模塊分解的線性規劃方程來解決PNC網絡的調度問題。從性能評估中我們發現了三個重要結論： 第一，PNC分解的輸出效率遠高於傳統的多步傳輸和普通的網絡編碼傳輸。例如，在網絡運輸量很重的情況下，相比于傳統的多步傳輸，PNC分解傳輸可以取得100%輸出增益。第二，基於多種不同PNC模塊的分解傳輸，其效率高於只基於PNC TWRC的分解傳輸。第三，在我們研究的九個模塊中，三個模塊對輸出的貢獻最多。我們同時為PNC調度專門設計了介質訪問控制（MAC）的網絡協議。 / 研究第三步，我們研究了PNC系統的自動重傳請求（ARQ）設計。上述的PNC模塊研究假設了網絡的傳送總能被成功接收。但不符合實際的網絡狀況。需要採取錯誤控制來保護實際傳輸的穩定性。這裡，我們致力於研究用ARQ來保證PNC系統的穩定傳輸。在一些PNC模塊中，接受點可以利用旁聽到的信息包裹來解碼編碼過的包裹以獲得需要的自然包裹。這種對於旁聽信息的利用可以增加網絡的傳輸效率。同時也使PNC系統的ARQ設計不同於傳統網絡。在本論文中，我們列舉了三個基本的PNC ARQ設計原則： 1）我們強調了如何追蹤存儲的和旁聽到的信息包裹來增加提取有效包裹的機會并推導出了由此取得效率增益。 2）我們研究了兩種PNC ARQ系統，一種是綁定的ARQ，一種是非綁定的ARQ,并證明非綁定的ARQ效率更高。 3）我們展示了如何優化PNC ARQ的參數設置——傳輸窗口的大小和確認通知（ACK）的頻率——以最小化由ACK開銷和不必要的重傳引起的輸出損失。 / 總結來講，基於不同PNC模塊的網絡分解調度方法比傳統的多步傳輸方法和普通的網絡編碼傳輸更有效率。在實際的無線網絡中，當網絡傳輸出現錯誤時，採用我們的PNC自動重傳設計可以有效的保留PNC模塊分解所取得網絡增益。 / He, Jianghao. / Thesis Ph.D. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 126-128). / Abstracts also in Chinese. / Title from PDF title page (viewed on 24, October, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

Sun, Qifu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 95-99). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

In coding theory we wish to find as many codewords as possible, while simultaneously maintaining high distance between codewords to ease the detection and correction of errors. For linear codes, this translates to finding high-dimensional subspaces of a given metric space, where the induced distance between vectors stays above a specified minimum. In this work I describe the recent advances of this problem in the contexts of lexicodes and Ferrers diagram rank-metric codes. In the first chapter, we study lexicodes. For a ring R, we describe a lexicographic ordering of the left R-module Rn. With this ordering we set up a greedy algorithm which sequentially selects vectors for which all linear combinations satisfy a given property. The resulting output is called a lexicode. This process was discussed earlier in the literature for fields and chain rings. We describe a generalization of the algorithm to finite principal ideal rings. In the second chapter, we investigate Ferrers diagram rank-metric codes, which play a role in the construction of subspace codes. A well-known upper bound for dimension of these codes is conjectured to be sharp. We describe several solved cases of the conjecture, and further contribute new ones. In addition, probabilities for maximal Ferrers diagram codes and MRD codes are investigated in a new light. It is shown that for growing field size, the limiting probability depends highly on the Ferrers diagram.